Device and method for controlling compressor of vehicles based on acceleration condition of vehicle

ABSTRACT

A device and a method for a controlling compressor of vehicles may include a cabin temperature sensor, an outdoor temperature sensor, an evaporator temperature sensor, an engine speed sensor, and a throttle position sensor detecting a throttle opening, a condenser, an evaporator, a temperature control door controlling a temperature of an air flowed in a cabin, an intake door selectively flowing an inner air or an outer air in the cabin, and a blower blowing the air to the intake door, and a controller controlling an operation of the air conditioning system, wherein the controller decides a acceleration mode and an allowable temperature at each acceleration mode when an acceleration condition occurs, and decreases an operation of the compressor according to a difference between the evaporator temperature and the allowable temperature.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2010-0063133 filed in the Korean IntellectualProperty Office on Jun. 30, 2010, the entire contents of whichapplication is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a device and a method for controlling acompressor of vehicles, and more particularly, to a device and a methodfor a controlling compressor of vehicles which improves accelerationperformance and fuel efficiency and maintains comfort of a cabin bydecreasing an operation of the compressor when accelerating.

2. Description of the Related Art

Recently, countries tighten exhaust regulations and fuel efficiencyregulations so as to retard progress of global warming and to preparedepletion of petroleum resources. In order to enhance fuel efficiency,improvement of auxiliary machinery including a powertrain is required.An air conditioning system including an air conditioner is one of suchauxiliary machinery.

Such air conditioning systems include a compressor. The compressorselectively receives an engine torque transmitted through a pulley byengaging or disengaging operation of an electric clutch and compresses acooling medium flowing in from an evaporator. After that, the compressorflows the cooling medium out to a condenser. Various types ofcompressors exist, and compressors of variable-capacity type are widelyused for vehicles.

According to the compressor of variable-capacity type, a pressurecontrol valve changes pressure of the cooling medium based on a load,and thereby, an angle of an inclined plate can be controlled. If theangle of the inclined plate is changed, stroke of a piston changes, andaccordingly, discharge flux of the cooling medium can also becontrolled.

A great amount of driving torque is required for operating thecompressor. Particularly, since the compressor receives the drivingtorque by the pulley connected to a crankshaft of an engine through abelt, the compressor is operated according to an engine speed irrelevantto a target cooling performance. In addition, since occupants operatethe air conditioning system for their comfort, the compressor mayoperate excessively and fuel efficiency may be deteriorated. Theseproblems mainly occur when acceleration or deceleration.

The information disclosed in this Background section is only forenhancement of understanding of the general background of the inventionand should not be taken as an acknowledgement or any form of suggestionthat this information forms the prior art already known to a personskilled in the art.

SUMMARY OF THE INVENTION

The present invention has been made in an effort to provide a device anda method for controlling a compressor of vehicles having advantages ofimproving acceleration performance and fuel efficiency and maintainingcomfort of a cabin by decreasing an operation of the compressor whenaccelerating.

Various aspects of the present invention are directed to a device forcontrolling a compressor of vehicles that may include a sensor moduleincluding a cabin temperature sensor detecting a cabin temperature ofthe vehicle, an outdoor temperature sensor detecting an outdoortemperature of the vehicle, an evaporator temperature sensor detecting atemperature of a cooling medium in an evaporator (evaporatortemperature), an engine speed sensor detecting rotation speed of anengine, and a throttle position sensor detecting a throttle opening, anair conditioning system including a condenser condensing and liquefyingthe cooling medium, an evaporator evaporating the liquefied coolingmedium, the compressor compressing the cooling medium, a temperaturecontrol door controlling a temperature of an air flowed in a cabin ofthe vehicle, an intake door selectively flowing an inner air or an outerair in the cabin of the vehicle, and a blower blowing the air to theintake door, and a controller controlling an operation of the airconditioning system, wherein the controller decides a acceleration modeand an allowable temperature at each acceleration mode when anacceleration condition occurs, and decreases an operation of thecompressor according to a difference between the evaporator temperatureand the allowable temperature.

The allowable temperature at each acceleration mode may be decidedaccording to the outdoor temperature of the vehicle.

The temperature control door may be controlled to lower the temperatureof the air supplied to the cabin when the evaporator temperature ishigher than a target temperature during decreasing the operation of thecompressor.

Control of the temperature control door by the controller may includecontrol of the intake door through which the inner air or the outer airselectively flows in the cabin and control of blowing speed of theblower.

The controller may increase the operation of the compressor according toa target increasing rate of the operation of the compressor when arelease condition occurs during decreasing the operation of thecompressor or a time spent decreasing the operation of the compressor islarger than or equal to a maximum time.

The controller may increase the operation of the compressor until theoperation of the compressor reaches to a target operation of thecompressor.

The controller may control the temperature control door to lower thetemperature of the air supplied to the cabin when the evaporatortemperature is higher than a second target temperature during increasingthe operation of the compressor.

The control of the temperature control door by the controller mayinclude the control of the intake door through which the inner air orthe outer air selectively flows in the cabin and the control of blowingspeed of the blower.

Various aspects of the present invention are directed to a method forcontrolling a compressor of vehicles that may include a) determiningwhether an acceleration condition occurs, b) determining whether anevaporator temperature is lower than an allowable temperature in a casethat the acceleration condition occurs, c) decreasing the operation ofthe compressor based on a difference between the evaporator temperatureand the allowable temperature when the evaporator temperature is lowerthan the allowable temperature, d) determining whether the evaporatortemperature is higher than a target temperature while the operation ofthe compressor is decreased, and e) controlling the temperature controldoor, the intake door, and the blower so as to lower the temperature ofthe air supplied to the cabin when the evaporator temperature is higherthan the target temperature.

The allowable temperature may be varied according to an accelerationmode decided based on a throttle opening and an engine speed, and theallowable temperature at each acceleration mode may be decided accordingto the outdoor temperature of the vehicle.

The intake door may be controlled based on a difference between thecabin temperature and the outdoor temperature or the outdoortemperature, and the blower may be controlled based on an inner airratio at the step e).

The method for controlling the compressor of the vehicles may furtherinclude g) determining whether a release condition occurs or a timespent decreasing the operation of the compressor is larger than or equalto a maximum time, wherein the steps b) to e) are repeated when therelease condition does not occur or the time spent decreasing theoperation of the compressor is smaller than the maximum time at the stepg).

In a case that the evaporator temperature is higher than or equal to theallowable temperature at the step b) or the release condition occurs orthe time spent decreasing the operation of the compressor is larger thanor equal to the maximum time at the step g), the method may furtherinclude h) increasing the operation of the compressor according to atarget increasing rate of the operation of the compressor, i)determining whether the operation of the compressor is lower than atarget operation of the compressor, j) determining whether theevaporator temperature is higher than the target temperature when theoperation of the compressor is lower than the target operation ofcompressor, and k) controlling the temperature control door, the intakedoor, and the blower so as to lower the temperature of the air suppliedto the cabin when the evaporator temperature is higher than the targettemperature.

The steps h) to k) may be repeated when the evaporator temperature islower than or equal to the target temperature at the step j) or the stepk) is performed.

The intake door may be controlled based on the difference between thecabin temperature and the outdoor temperature or the outdoortemperature, and the blower may be controlled based on the inner airratio at the step k).

Controlling the compressor may be finished when the operation of thecompressor reaches the target operation of the compressor at the stepi).

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description of the Invention, which togetherserve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an exemplary device for controlling acompressor of vehicles according to the present invention.

FIG. 2 is a graph explaining the spirit of the present invention.

FIG. 3 is a flowchart of an exemplary method for controlling acompressor of vehicles according to the present invention.

FIG. 4 is a map showing a condition of a throttle opening and an enginespeed entering or releasing from each acceleration mode.

FIG. 5 is a graph showing an allowable temperature according to anoutdoor temperature at each acceleration condition.

FIG. 6 is a graph showing a relation between an operation of acompressor and a temperature difference.

FIG. 7 is a graph showing an inner air ratio according to a temperaturedifference.

FIG. 8 is a graph showing a blower speed respectively at an outer airmode, a partial inner air mode, and an inner air mode.

FIG. 9 is a graph showing an operation of a compressor to time.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

As shown in FIG. 1, a device for controlling a compressor of vehiclesaccording to various embodiments of the present invention includes asensor module 10, a control portion 20, an actuator 30, an airconditioning system 40, and an injector 50.

The sensor module 10 includes a cabin temperature sensor 11, an outdoortemperature sensor 13, an evaporator temperature sensor 15, an enginespeed sensor 17, and a throttle position sensor 19. Additionally, thesensor module 10 further includes sensors for shifting (e.g., a vehiclespeed sensor, a brake sensor, and so on) and/or sensors for controllingan engine (e.g., an exhaust temperature sensor, an oxygen sensor, and soon).

The cabin temperature sensor 11 detects a cabin temperature of thevehicle and transmits a signal corresponding thereto to the controlportion 20.

The outdoor temperature sensor 13 detects an outer temperature of thevehicle and transmits a signal corresponding thereto to the controlportion 20.

The evaporator temperature sensor 15 detects a temperature of a coolingmedium passing through an evaporator and transmits a signalcorresponding thereto to the control portion 20.

The engine speed sensor 17 detects a rotation speed of an engine from aphase change of a crankshaft, and transmits a signal correspondingthereto to the control portion 20.

The throttle position sensor 19 detects a throttle opening according toan operation of an accelerator pedal, and transmits a signalcorresponding thereto to the control portion 20.

The control portion 20 is electrically connected to the sensor module 10so as to receive signals corresponding to values detected by the sensormodule 10, and controls the injector 50 and the air conditioning system40 based on the signals. Various control units such as a transmissioncontrol unit controlling a transmission of the vehicle, an enginecontrol unit controlling the engine, and an air conditioning systemcontrol unit controlling the air conditioning system 40 may be used inthe vehicle, and the control portion 20 in this specification includesall the control units used in the vehicle. Particularly, it is to beunderstood that the control portion 20 includes all the control portionssuitable to perform a method for controlling a compressor according tovarious embodiments of the present invention.

The actuator 30 is electrically connected to the control portion 20 andoperates the air conditioning system 40 and/or the injector 50 accordingto a control signal transmitted from the control portion 20. A solenoiddevice may be used as the actuator 30, and the control signal may be aduty signal applied to the solenoid device.

The air conditioning system 40 includes all the devices used forwarming, ventilating, and cooling the cabin of the vehicle. Concretely,the air conditioning system 40 includes a condenser 41, an evaporator43, a compressor 45, a temperature control door 47, an intake door 48,and a blower 49. The air conditioning system 40 may include variouscomponents which are not described in this specification.

The condenser 41 condenses and liquefies the cooling medium, theevaporator 43 evaporates the liquefied cooling medium, and thecompressor 45 compresses the cooling medium.

In addition, the temperature control door 47 controls a temperature ofan air supplied to the cabin of the vehicle by mixing a warm air with acool air, the intake door 48 controls an inner air, an outer air or amixture of the inner and outer airs to flow in the cabin of the vehicle,the blower 49 blows the air toward the intake door.

Such an air conditioning system 40 is well known to a person of anordinary skill in the art, and a detailed description thereof will beomitted.

The injector 50 injects a fuel so as to drive the vehicle (particularly,the engine).

A solid line in FIG. 2 represents a cooling performance and an operation(load) of the compressor according to a conventional art, and a dottedline represents a cooling performance and an operation (load) of thecompressor according to various embodiments of the present invention.

If an acceleration condition of the vehicle occurs, the engine speedincreases excessively and the compressor also operates excessivelyaccording to a conventional art. Therefore, a cooling performance andthe operation (load) of the compressor increases excessively.

If the acceleration condition of the vehicle occurs, the operation(load) of the compressor is gradually increased to a target operation ofthe compressor after being decreased by a predetermined value accordingto the spirit of the present invention. Accordingly, the coolingperformance is increased to a target cooling performance slowly afterbeing decreased temporarily. Since an excessive operation of thecompressor is prevented and power spent in operating the compressor isreduced if the acceleration condition of the vehicle occurs,acceleration performance and fuel efficiency may be improved.

A method for controlling a compressor for vehicles realizing the spiritof the present invention will be described with reference to FIG. 3 toFIG. 9.

As shown in FIG. 3, in a state that the vehicle runs, the controlportion 20 controls the cabin temperature of the vehicle at a step S110.At this state, the control portion 20 determines whether theacceleration condition occurs at a step S120. The acceleration condition(solid line) and the release condition (dotted line) at eachacceleration mode are shown in FIG. 4. Such acceleration condition andrelease condition according to the engine speed and the throttle openingare defined in a map. According to various embodiments of the presentinvention, the control portion 20 determines the acceleration mode in acase that the acceleration condition is satisfied so as to improveaccuracy of control of the compressor. Such the acceleration modeincludes a quick acceleration mode and a slow acceleration mode. Theacceleration mode may further be subdivided, if necessary.

In addition, as shown in FIG. 4, an entry condition and a releasecondition are set differently at each acceleration mode. Frequent changeof control states may be prevented by differently setting the entrycondition and the release condition at each acceleration mode. That is,if the entry condition and the release condition are same at eachacceleration mode, the control state may change frequently in a casethat the engine is operated at a boundary of the acceleration condition.Thereby, fuel efficiency may be deteriorated. Therefore, the frequentchange of the control state and deterioration of fuel efficiency may beprevented by differently setting the entry condition from the releasecondition at each acceleration mode.

The step S120 will further be described in detail. The control portion20 determines whether a quick acceleration mode entry condition occursor a slow acceleration mode entry condition occurs when the accelerationcondition occurs. The reason why the acceleration modes are decided asdescribed above is that an allowable temperature which is the basis of adecrease control of the operation of the compressor is differently setat each acceleration condition (referring to FIG. 5).

If the acceleration condition does not occur at the step S120, thecontrol portion 20 continues to perform a cabin temperature control atthe step S110.

If the acceleration condition occurs at the step S120, the controlportion 20 decides the acceleration mode and the allowable temperatureat each acceleration mode as shown in FIG. 5.

The allowable temperature means an evaporator temperature correspondingto the temperature of the air required for maintaining the comfort ofthe cabin. If the operation of the compressor is decreased after theacceleration condition occurs, the temperature of the air supplied tothe cabin increases. Therefore, the operation of the compressor shouldbe increased again in order to lower the temperature of the air suppliedto the cabin. This deteriorates fuel efficiency. In order to solve suchproblems, the operation of the compressor must be decreased until theevaporator temperature reaches the allowable temperature.

Such an allowable temperature at each acceleration mode is decidedaccording to the outdoor temperature of the vehicle. If the outdoortemperature of the vehicle is low, the temperature of the air suppliedto the cabin can be sufficiently lowered by controlling the temperaturecontrol door 47, the intake door 48, and the blower 49 withoutincreasing the operation of the compressor even if the allowabletemperature of the evaporator is high.

Meanwhile, the allowable temperature at the quick acceleration mode ishigher than that at the slow acceleration mode under the same outdoortemperature. Since a large amount of torque is spent in acceleration atthe quick acceleration mode, the cooling performance is reduced slightlyand the acceleration performance is improved by setting the allowabletemperature to be high at the quick acceleration mode.

If the allowable temperature is decided as described above, the controlportion 20 determines whether the evaporator temperature is lower thanthe allowable temperature at a step S130. If the evaporator temperatureis higher than or equal to the allowable temperature at the step S130,the control portion 20 proceeds to a step S180 and does not decrease theoperation of the compressor. If the evaporator temperature, on thecontrary, is lower than the allowable temperature at the step S130, thecontrol portion 20 decreases the operation of the compressor at a stepS140. The operation of the compressor, as shown in FIG. 6, is decreasedbased on a difference between the evaporator temperature and theallowable temperature. That is, the decrease of the operation accordingto the temperature difference is defined in a map. Herein, it isexemplary shown that the operation amount is proportional to thetemperature difference, but the spirit of the present invention is notlimited to this.

After that, the control portion 20 determines whether the evaporatortemperature is higher than a target temperature at a step S150.Generally, if the operation of the compressor decreases, the evaporatortemperature is raised and the temperature of the air supplied to thecabin is also raised. Thereby, comfort of the cabin may be deteriorated.Therefore, if the evaporator temperature is higher than the targettemperature at the step S150, the control portion 20 controls thetemperature control door 47, the intake door 48, and the blower 49 so asto suppress a rise of the temperature of the air supplied to the cabinat a step S160. That is, the temperature control door 47 is controlledbased on the difference between the temperature of the air supplied tothe cabin at the step S110 and the current temperature of the airsupplied to the temperature control door 47. The intake door 48, asshown in FIG. 7, is controlled based on a difference between the cabintemperature and the outdoor temperature or the outdoor temperature. Aspeed of the blower 49, as shown in FIG. 8, is controlled based on aninner air ratio (a ratio of the inner air to the air supplied to thecabin).

Explaining concretely, the temperature control door 47 is controlled tolower the temperature of the air supplied to the cabin. For thispurpose, a ratio of the inner air and the outer air is controlledthrough the intake door 48, and speeds of the inner air and the outerair are controlled through the blower 49.

If the evaporator temperature is lower than the target temperature atthe step S150, the control portion 20 does not control the temperaturecontrol door 47, the intake door 48, and the blower 49 and proceeds to astep S170.

At the step S170, the control portion 20 determines whether the releasecondition occurs or the time spent in decreasing the operation of thecompressor is larger than or equal to a maximum time. If the releasecondition does not occur or the time spent in decreasing the operationof the compressor is smaller than the maximum time, the control portion20 continuously performs the steps S130 to S170, repeatedly.

Meanwhile, if the release condition occurs at the step S170, the controlportion 20 proceeds to the step S180 because an operation of theevaporator cannot be decreased. In addition, the time spent indecreasing the operation of the compressor is larger than or equal tothe maximum time at the step S170, the control portion 20 decides thatthe accelerations are continuously performed (e.g., in a case that thevehicle runs uphill), and proceeds to the step S180 for the comfort ofthe cabin.

Steps S180 to S210 are steps for preparing a normal operation of thecompressor 45. If the evaporator temperature is higher than or equal tothe allowable temperature at the step S130, the temperature of the airsupplied to the cabin is higher than that of the air required formaintaining the comfort of the cabin. In this case, the temperature ofthe air supplied to the cabin is lowered by raising the operation of thecompressor to a target operation of the compressor and the cabintemperature control is performed normally. At this time, if theoperation of the compressor is raised quickly, the injection amount ofthe fuel increases. Therefore, the operation of the compressor isgradually increased so as to prevent the fuel efficiency and the comfortfrom being deteriorated.

For this purpose, the control portion 20 increases the operation of thecompressor according to a target increasing rate of the operation of thecompressor at the step S180. The target increasing rate of the operationof the compressor, as shown in FIG. 9, is calculated according to atarget position of the temperature control door 47 and a referencetarget increasing rate of the operation of the compressor. The targetincreasing rate of the operation of the compressor A_(rate) isrepresented as a dotted line in a right graph in FIG. 9. That is,assuming that a distance from a predetermined position of thetemperature control door when the outdoor temperature is 0° C. to thetarget position of the temperature control door is α and a distance fromthe predetermined position of the temperature control door when theoutdoor temperature is 0° C. to a minimum position of the temperaturecontrol door is β, the target increasing rate of the operation of thecompressor A_(target) is calculated from a following equation.A _(target) =A _(rate)*(α/β)  Eq. (a)

The reference target increasing rate of the operation of the compressorA_(rate) represents an increasing rate of the operation of thecompressor used for increasing the operation of the compressor at anormal state. Since the operation of the compressor is increasedaccording to the target increasing rate of the operation of thecompressor A_(target) that is lower than the reference target increasingrate of the operation of the compressor in various embodiments of thepresent invention, the operation of the compressor may be prevented frombeing increased quickly. Therefore, deterioration of the fuel efficiencymay be prevented.

After performing the step S180, the control portion 20 determineswhether the operation of the compressor is lower than the targetoperation of the compressor at the step S190. That is, it is determinedwhether the operation of the compressor reaches the target operation ofthe compressor. If the operation of the compressor reaches the targetoperation of the compressor at the step S190, the control portion 20finishes the method for controlling the compressor according to variousembodiments of the present invention and returns to the step S110. Ifthe operation of the compressor is lower than the target operation ofthe compressor at the step S190, the control portion 20 determineswhether the evaporator temperature is higher than the target temperatureat the step S200.

If the evaporator temperature is lower than or equal to the targettemperature at the step S200, the control portion 20 continuouslyperforms the steps S180 to S200, repeatedly.

If the evaporator temperature is higher than the second targettemperature at the step S200, the control portion 20 controls thetemperature control door 47, the intake door 48, and the blower 49 so asto suppress the rise of the temperature of the air supplied to the cabinat the step S210. Since the step S210 is the same as the step S160, adetailed description thereof will be omitted.

According to the present invention, an operation of a compressor isdecreased when accelerating. Therefore, acceleration performance andfuel efficiency may be improved.

In addition, a temperature control door, an intake door, and a blowerare controlled so as to prevent a temperature rise of an air supplied toa cabin according to a decrease of an operation of a compressor.Therefore, comfort may be secured.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

What is claimed is:
 1. A device for controlling a vehicle compressor,comprising: a sensor module including a cabin temperature sensordetecting a cabin temperature of a vehicle, an outdoor temperaturesensor detecting an outdoor temperature of the vehicle, an evaporatortemperature sensor detecting an evaporator temperature, an engine speedsensor detecting rotation speed of an engine, and a throttle positionsensor detecting a throttle opening; an air conditioning systemincluding a condenser condensing and liquefying a cooling medium, anevaporator evaporating the liquefied cooling medium, the compressorcompressing the cooling medium, a temperature control door controlling atemperature of air flowed in a cabin of the vehicle, an intake doorselectively distributing inner air or outer air into the cabin of thevehicle, and a blower blowing the inner air or the outer air to theintake door; and a controller controlling an operation of the airconditioning system; wherein the controller decides a plurality ofacceleration modes and a temperature at each acceleration mode when anacceleration condition occurs, and, when the acceleration conditionoccurs, the controller decreases an operation of the compressoraccording to a difference between the evaporator temperature and thedecided temperature, wherein the acceleration condition is a conditionin which the rotation speed of the engine increases, and wherein theacceleration modes include differently predetermined accelerations inthe rotation speed of the engine.
 2. The device of claim 1, wherein thedecided temperature at the each acceleration mode is decided accordingto the outdoor temperature of the vehicle.
 3. The device of claim 1,wherein the controller controls the temperature control door to lowerthe temperature of the air flowed in the cabin when the evaporatortemperature is higher than a target temperature during decreasing theoperation of the compressor.
 4. The device of claim 3, wherein controlof the temperature control door by the controller comprises control ofthe intake door through which the inner air or the outer air selectivelyflows in the cabin and control of blowing speed of the blower.
 5. Thedevice of claim 1, wherein the controller increases the operation of thecompressor according to a target increasing rate of the operation of thecompressor when a release condition occurs during decreasing theoperation of the compressor or a time spent decreasing the operation ofthe compressor is larger than or equal to a maximum time.
 6. The deviceof claim 5, wherein the controller increases the operation of thecompressor until the operation of the compressor reaches to a targetoperation of the compressor.
 7. The device of claim 5, wherein thecontroller controls the temperature control door to lower thetemperature of the air flowed in the cabin when the evaporatortemperature is higher than a second target temperature during increasingthe operation of the compressor.
 8. The device of claim 7, wherein thecontrol of the temperature control door by the controller comprisescontrol of the intake door through which the inner air or the outer airselectively flows in the cabin and control of blowing speed of theblower.